This invention relates to an amorphous alloy which is suitable for use in a magnetic head and is of improved abrasion-resistance.
Heretofore, as a material of high permeability and suited for use in a magnetic head, there have been known a Fe-Ni alloy (Permalloy), a Fe-Si-Al alloy (Sendust) and the like which are crystalline. However, the Fe-Ni alloy is high in permeability on the one hand and poor in abrasion-resistance on the other hand; the Fe-Si-Al alloy is excellent in abrasion-resistance, but is too brittle to be plastically workable.
Taking the place of these alloys, an amorphous alloy, which is non-crystalline, has been found to have excellent mechanical and magnetic properties when used as the material for a magnetic head, and it has recently been acknowledged as a new material. However, despite its high Vickers hardness which in general reaches a value as large as 1000, it has been known, and has been a serious problem in practice, that the material is seriously worn by friction with a tape when it is used for a magnetic head.
The mechanism of abrasion of a magnetic head where such an amorphous alloy is used therefor has ever been discussed from a variety of viewpoints, and it has been considered that the abrasion is caused principally by mechanical factors and chemical factors. As a result of studies, however, no relationship is observed between Vickers hardness of the amorphous alloy and the quantity or degree of abrasion (i.e. abrasion-resistance) thereof, and it is considered that the abrasion is more greatly influenced by the chemical factors. For this reason, the advent of the amorphous alloy having higher abrasion-resistance to the wear of head caused by the chemical factors, has long been desired.